A method as described above is disclosed in International Patent Application nr. WO 01/88739, describing a personal service environment manager (PSEM). The document describes an open service architecture (OSA) comprising service capabilities servers and service provisioning servers or application servers. The document further describes the underlying network technology consisting of service switching points, and the setting up of services through one or more service capability servers interacting with the service provisioning servers or application servers.
The number of services that can be offered over telecommunications networks and the integration of the services within modern society has increased rapidly over the past decennia. Services are becoming more and more sophisticated, and can be accessed by any user from any location at any point in time. The introduction of the universal mobile telecommunications system (UMTS) has accelerated this development even more.
In general, in a telecommunications system, services are offered over the network using service capability servers (SCS). These service capability servers are responsible for management of the service and the telecommunications infrastructure required to provide that service. In the hierarchy below the service capability servers, the telecommunications infrastructure is comprised of service switching points (SSP), which are interconnected with each other. Service provisioning equipment, such as media servers, and user equipment, like a telephone set or a mobile phone, also connects to the service switching points.
In recent years, UMTS has triggered the development of the so-called open service architecture (OSA), in which service providers can easily incorporate the services offered by a third party into there own service without having to reveal this to their customers. The customer will only deal with one provider from which he receives support, and which provider sends him one bill for all the services used. The use of this principle is not limited to UMTS. Those skilled in the art will appreciate that similar methods can be used in any telecommunications system.
According to the open service architecture principle the user calls, for instance, to an application server, and accesses an application that provides the user with a choice of services. These services could be voice mail service, fax service, IP services, multi media, etc. As explained above, the provisioning of services itself over the telecommunications infrastructure is managed by service capability servers, and this is also the case for applications on an application server, which is accessed by users.
As more complicated services are made up of interactions on different levels of communications, call control, user interaction, etc, each service capability (level/type of communication) may be handled by a different service capability server. A number of these service capability servers may be operated from the same location on the network, e.g. being part of a framework, but in some cases in order to offer a service a plurality of service capability servers are used from different locations.
It is best to consider an example to illustrate this principle. Take for example the user calling into an application. First, the connection between the user and the application will be set up by a call control service capability server. As soon as this connection has been established the application will, for example, start a security authentication procedure. This security authentication procedure may consist of a digitised voice message after which the user can enter his pin code via dual tone multi-frequencies (DTMF) on the keyboard of his telephone set. Suppose however that the authentication procedure will not be handled by the application itself, but by a remote media server. In order to perform this action, the application needs to contact a remote user interaction service capability server. This service capability server may be in a different location than the service capability server that has established the call between the application and the user. The application knows exactly which service capability server to contact in order to start the authentication procedure. Ideally the application only temporarily transfers the call to the media server, responsible for carrying out the security authentication procedure, and take back the call after the procedure has ended. The transfer of a call is handled, as mentioned, by the call control service capability server. The problem is that the user interaction service capability server knows where the media server is, and the call control server, handling all details of the user call, needs to transfer the call whilst maintaining contact to the application. In this case an extra speech channel needs to be set up between the service switching point and the media server.
In an existing solution, the location details of the media server are offered by the user interaction service capability server to the application, and the application, on his turn, forwards this information to the call control service capability server. Upon receiving this information the call control service capability server instructs the service switching point to open a speech channel to the media server as it now knows where this media server is located.
The major issue with this solution is that the application is involved in the management of the telecommunication services, while in principle, the underlaying telecommunications infrastructure needs to be transparent to the application, as well as to the user.